Rayon spinning machine



April 7, 1953 1.. ROSE ETAL 2,633,694

-RAYON SPINNING MACHINE.

Filed Dec. 27, 1951 Y s Sheets-Sheet 1 In van fors Leslie Rose 15 Eric John Why/e MMM April 7, 1953 ROSE ET AL RAYON SPINNING MACHINE 5 Sheets-Sheet 2 Filed Dec. 27, 1951 FIGZ.

lnven/ors.

Leslie Rose Eric John Why/e By fire/r afforn e ys April 7, 1953' L. ROSE ET AL RAYON SPINNING MACHINE 3 Sheets-Sheet 3 Filed Dec. 27, 1951 Fl I35 W lnven/ors FIGE.

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By their attorneys which results in faulty cakes.

Patented Apr. 7, 1953 RA zoN SPINNING MACHINE Leslie Rose, Whitefield, near Manchester, and Eric J. Whyte, Coventry, England, assignors to Courtaulds Limited, London, England, a British company Application December 2'7, 1951, Serial No. 263,568

In Great Britain November 5, 1948 2 Claims. (CI. 57-76) This invention relates torayon spinning machines and is particularly concerned with the traverse mechanism by which'the funnel feedin the extruded filaments into a rotating spinning box is traversed through the action of followers on a cam; This application is a continuation-inpart application of our application, SerialNo.

120,904, filed October 12, 1949, now abandoned.

' In accordance with conventional practice the rounding over an angle of some 3 is not sufficient to interrupt in any material way the steady traversing action so that a cake with substantially cylindrical and parallel surfaces is obtained. In

practice it is usual to make the height of the spinning box slightly greater than the stroke of the thread guide, for example, with a stroke of 4.49 inches the height of the box is normally 4.6 inches. With existing apparatus it has now been found that there is a maximum permissible speed I at about 32 beats per minute and above this speed there is excessive vibration of the thread guides One cause is the fact that the acceleration given to the cam-follower at speeds above 32 beats per minute exceeds the acceleration due to gravity (9) at the tip and at the root of the cam.

In standard pot spinning machines, two banks of funnels are reciprocated by two cams arranged at the ends of the banks. Each cam has a follower, and the two followers are arranged on a traverse bar 30 (in Fig. 4 of this application) In practice one cam Will wear more than the other, so that one cam follower will not in practice completely follow the contour of its cam, but will be influenced by the other follower to leave the surface of the cam and crashes back on to it after a short aerial path. The shock is transmitted to the traverse rail which thus vibrates with its own natural frequency.

The specification of co-pending application, Serial No. 255,388, filed November 8, 1951 (now Patent No. 2,633,693) which is a continuation-inpart of application, Serial No. 54,626, filed October 15, 1948, and now abandoned, describes and claims a rayon centrifugal spinning machine comprising a spinning box, a thread guide for feeding filaments to the spinning box and a camfollower for traversing the thread guide axially 'of the spinning box in which machine there is provided the combination'of a cam activating said cam follower, said cam being rounded off at the tip and the root over angles of at least 10 (preferably 15) whereby the stroke of the guide has an appreciable dwel1 at each end and filaments are accumulated at the top and bottom of the box, and means for adjusting the height of the box with respect to the stroke of the cam so that the stroke of the guide is substantially shorter than the height ofthe spinning box in such degree'that automatic spreading out of the accumulated filaments occurs and a cake having inside and outside surfaces substantially cylindrical and parallel is obtained. The spinning machine described in the said specification permits the use of speeds of the order of 48 beats per minute. I

It is the object of the present invention to provide improved spinning machines capable of op.- erating at even higher speeds.

According to the present inventionv a rayon spinning machine comprising a spinning box. a funnel for feeding filaments to the spinning box and a cam follower for traversing the funnel axially of the spinning box is providedwith the combination of a funnel for feeding extruded filaments to said box and having its feeding edge indented, a cam activating said cam follower, said cam being rounded off at the tip and root over angles of from about 14 to about 30, whereby the stroke of the guide has an appreciable dwell at each end and filaments are accumulated at the top and bottom of the box, and means for adjusting the height of the box -with respect to the stroke of the cam so that the stroke of the guide is substantially shorter than the height of the spinning box; the shortened stroke ofthe guide and the corrugations of the funnel combining to cause automaticspreading out of the accumulated filaments and the formation of a cake having inside andoutside surfaces substantially cylindrical and parallel.

The use of a funnel having an undulating or indented edge in accordance with the invention in'general permits the production of cakes with substantially parallel sides by the use of cams which are rounded off over angles of 14 to 30, Cams rounded off over angles of from 22 to 30 have been used satisfactorily in machines according to the invention operating at spinning speeds of the order of to '70 beats per minute or even higher. I l

The cams employed in the present invention are preferably so rounded off that the modified cam surfaces follow an arc of a'circle in such a way that its tangents at the points where rounding begins are coincident with the tangents to the true cardiac curve; by so rounding off, the modified cam surfaces at the tip and the root to all intents and purposes follow the curve of a constant acceleration cam so that the cam used is in effect a combination of a constant velocity cam and a :constant acceleration cam, the .latter forming the tip and root of the composite cam, preferably over angles of the order of 22 to 30. In an alternative form of cam, the tip of the cam is rounded off over an are -as'described above but the root of the cam ismade flat.

With the rayon spinning machines according to the invention, it is importantkthat the itravarse-stroke of the funnel should be sufficiently shorter than the height of the box to permit the automatic spreading out of'the accumulated=filaments in the box to give a cake of uniform thickness. The adjustment of the height of ethe'box relative to the stroke of the thread guide may #conveniently be made as described in application, *TSQIla]. No. 255,388 by raising the bottom of the ffunnelithe normal thread guide employed) from the %floor1of the box to the required extent for example by holding the funnel in a ring held'by :aaiscrewed bush which can be screwed upwardly zorudownwardl-y so that the bottom of the fun- 'nel .iscorrespondinElYjmoved upwardly or downwardly, and providing the box with a lidhaving 3a irecess of substantially increased depth. Thus :witha'series of lids each 'with-a-different depth below therecess, provision may be made sothat adifierentitypes of cakes-can be collected with a single box. The difference between the height .ofz thenbox and the strok'eof the thread guide is preferably varied according to the denier of the thread :being. spun, the .higher the denier the greater the difference. This diiference maybe ascertained by simple :tests by varying-the posittion of the bottom of the funnel and using lids of different thicknesses.

Funnels having undulating or indented edges "suitableifor use the present invention :are described'in :United States Patent .No. 2,100,595.

l?he invention is illustrated by way .of examples in the accompanying diagrammatic draw- "in'g's in which:

Fig-lire ll is -a p'lanview of one form of cam suitable-for use in the presentin'vention, the-cam "being rounded off over angles of '30",

Figure 2*is a vertical section of a funnel and a=ceiitrif ugal spinning box,

Figure =3 is a plan -view of a further form of cam which is rounded 01? over angles of 22 /2",

Figure4 isa diagrammatic view on a reduced *sc'ale of a double-sided spinning machine 'in accordance with the invention comprising a r'ound- %ed-cam,-a cam follower, ;a traverse bar and-two funnels 'with undulating ends, and

Figures 5 and 6 show lids "having recesses of different depths to give the necessary adjustment bf -the height of the box -X.

Figu re l sho'ws a Cam 1 which apart 'f'romthe tip 2 and the-root 3 follows the sci-called true cardiac curve. The tip 2 and root 3 are both rounded on over :an angle a subtended at the Jcehtre i) of .the cam .I, a as "shown'being Chain lines :4 and 5. show the tip anderoot respectively of 5a true-cardiac curve and illustrate the g effectgofarounding off the cam in accordance-with the invention.

Referring to Figures 2 and A, ;-a reciprocating .yfunnel fiis used to lay a thread into a cen- .;trifugal:spinning box-,8 -to formpa cake 9. The -igunnel :;6 has an undulating :end .10, which rla-ys groove of the cam I.

downwardly as the case may be. box 8 ,is provided with a circumferential lip I8 ands. lid'l-l witharecess I9 of appreciable depth the thread I in the box 8, a stem part II and a cone-shaped part I2 which rests on a metal ring I3 in the top of of a bush I4. Bush I4 screws into a support I5 which is reciprocated by a bar I5 which, in accordance with standard practice'issecured toa follower .23 which runs in the The follower i 23 slides vertically on guides 24. Adjustment of the position of the funnel at the bottom of the stroke is obtained by screwing the bush I4 upwardly or The spinning and a central hole 20 for passage of the funnel '6. In accordance with the present invention the height of the box (X) is made longer than the lengthfYi) of the traverse stroke of the funnel 6 so that'the'thread I when formed into the cake 9, automatically spreads out to form a cake having substantially cylindrical and parallel inside and .outside surfaces. Other lids I], having recesses I9 and'jfi" ofdiffrent thicknesses are ;il-

lustrated in Figures ;5 and 6. I'n'order tocompensate for the effects of gravity at the ends of the stroke, the difference between the endpoints of ,X and Y at the top of the box is'made less than at theendpoints of X and Ylat the bottom of the box.

-Figure,3 shows a cam 25 which has-beenlround- -ed ofiat the tip 26 and therootll 'ove'rian angle 5 of '22; /2. Thenormal tip-and root of a true cardiac curve are-shown-in chain IinesatZBand 2:' l respectively. v I

The invention is illustrated by the following examplesin whichthepercentages are by-weight.

In Example 1 a cam having its tip and root rounded-off over 30 as shown in Figure 1 was used with :a spinning box .assembly and machine as shownin-Figures2 and-4; inrExample 2=a cam having its *root and tip rounded ofi over-22% as shown in Figure -3 was used, also .wit h the spinning box assembly and machine shown in Figures 2 and I 4.

Example 1 fViscose containing 8 :per cent of cellulose and 6.5 per cent of caustic soda, aged to a salt point of 6z0,-wasextruded through a jet con'tainin'g 27 holes, each five thousandths of an inch in diameter, intoa co agulant bath "at 50 'c'e'ntigrade colltain'ing -1 0 per cent of sulphuric acid, 18 per cent of sodium sulphate a-nd *1 per-c'e'n-t of zinc si'ulpirate, to produce a denier "thread. -The thread-*sdformedwas wahdrawmrom the bath a't asp'eed-of SB metres per minutes and was pa'ss'ed round "a gode't driven at such *a speed ""that the thread-was-stretched 25 per cent. From thegodet thethread-was passeda't aspeed-of 106i 25-metres per minute to a centrifugalfbo'x *8 rotating at 1,080 -revolutions per minute. The "thread wa's led into the box bymeans *ofia funnel 6 which had an undulating end Fa containing 8 undulations each of 2 mm. depth and which was traversed through a cam-follower 23 operated by the cam I having both its root "and tip rounded off ever {Despite the fact that the cam -I action and did not give rise to excessive vibration. The inside and outside surfaces of the cake of thread obtained were cylindrical and parallel and the cake was readily penetrated by the customary processing liquids such as for example washing liquids.

Example 2 Viscose containing 8 per cent of cellulose and 6.5 per cent of caustic soda, aged to a salt point of 5.8, was extruded through a jet containing 27 holes, each five thousandths of an inch in diameter, into a coagulant bath at 60 centigrade containing 9.5 per cent of sulphuric acid, 20 per cent of sodium sulphate and 1.5 per cent of zinc sulphate, to produce a 150 denier thread. The thread so formed was withdrawn from the bath at a speed of 95 metres per minute and was passed round a godet driven at such a speed that the thread was stretched 25 per cent. the godet the thread was passed at a speed of 118.75 metres per minute to a centrifugal box rotating at 7,000 revolutions per minute. The thread was led into the box by means of a funnel 6 which had an undulating end containing 8 undulations each of 2 mm. depth and which was traversed through a cam-follower operated by a cam 25 having both its root and tip rounded ofi" over angles of 22 as shown in Figure 3. The

rate of reciprocation of the funnel B was 65 beats per minute. The length of the traverse (Y) was 4.37 inches, the height of the box (X) was 4.71 inches and the funnel was set so that at the bottom of its stroke, the corrugated end It] was within 0.23 of an inch of the bottom of the box. De-

spite the fact that the cam 25 was operated at about twice the speed normally employed hitherto, the traverse was smooth in action and did not give rise to excessive vibration. The inside and outside surfaces of the cake of thread obtained were cylindrical and parallel and the cake was readily penetrated by the customary processing liquids such as for example washing liquids.

What we claim is:

1. In a rayon centrifugal spinning machine From I comprising a spinning box, a funnel for feeding filaments to the spinning box and a cam-follower for traversing the funnel axially of the spinning box, the combination of a funnel for feeding extruded filaments to said box and having its feeding edge indented, a cam activating said camfollower, said cam having the shape of a true cardiac curve except for the tip and the root, said cam being rounded ofi at the tip and root over angles of from about 14 to about 30, whereby the stroke of the guide has an appreciable dwell at each end and filaments are accumulated at the top and bottom of the box, and means for adjusting the height of the box with respect to the stroke of the cam so that the stroke of the guide is substantially shorter than the height of the spinning box; the shortened stroke of the guide and indentation of the funnel combining to cause automatic spreading out of the accumulated filaments and the formation of a cake having inside and outside surfaces substantially cylindrical and parallel.

2. A machine as claimed in claim 1 wherein the cam is rounded off at the tip and root over angles of from about 22 to 30.

LESLIE ROSE. ERIC JOHN WHYTE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,489,199 Dreaper Apr. 1, 1924 1,663,555 Jessen Mar. 27, 1928 2,100,595 Jansen Nov. 30, 1937 2,177,322 Jansen Oct. 24, 1939 2,443,231 Elvin et a1. June 15, 1948 FOREIGN PATENTS Number Country Date 526,642 Germany June 8, 1931 625,277 Germany Feb. 7, 1936 

